In broadcast and multicast digital TV, each TV channel is constructed of one or more programme streams (PS). Service information (for example, information relating to the content, scheduled time, or channel) is broadcast along with the TV channels themselves. Each PS is itself composed of individual programmes. A viewer experiences the broadcast programmes in a set order and at a predetermined time. The viewer is generally given access to an electronic programme guide (EPG), which is generated from the service information and which shows the programmes and/or channels and their schedule airtime. Through the selection of a channel within the EPG, the user can control the content displayed on a TV set.
Video on Demand (VoD) content is also structured as services for delivery in programme streams, which are experienced by viewers as channels. Each VoD programme stream initially presents a list of viewable content, i.e. a menu. In many cases, the menu is displayed within an EPG. Content items are selected for viewing from the menu, through user interaction with the EPG, for example. VoD content items are then generally downloaded as individual items from the list of items.
It is known to obtain broadcast programme streams, together with service information indicating constituent programmes, and to extract the respective programmes as content items for storage and later playback. The extracted content items can then be presented in the same way as any other VoD content item, i.e. as items on a list. Again, user selection of content items for viewing is facilitated through user interaction with an EPG.
It should be noted that the term “content item”, in the context of video output, includes: videos (e.g. movies, music videos, time-shifted TV programmes); promos; and stings (also referred to as interstitials). In broadcast television, advertisements and other interstitial content are often inserted between sections of main programmes by the broadcaster.
To facilitate user selection of programme/channel for viewing, conventional digital video delivery systems provide each viewer with a set top box (STB) device and an associated remote controller. The STB generates an EPG for displaying user options and programme schedules on a user playback device, such as a TV set. The remote controller is configured to adapt with the STB and has control buttons, so that a user may press a button on the remote control in order to control an action effected by the STB, the EPG presented on the TV set facilitating this selection and showing which action has been requested. Each customer or viewer interacts with a STB to control the viewing and receipt of video and other data. In some instances, the set top box functionality is integrated in the television set and control of the STB functionality is effected through the normal TV remote controller.
The interaction between user and STB is linear in the sense that the viewing of the content items on any given broadcast or VoD channel consists of selecting a content item then letting the content item stream onto the user display with no further input from the user.